RESUMEN
A Gram-stain negative, aerobic, rod-shaped, non-motile, yellow-pigmented and non-spore-forming bacterial strain, designated PM5-8T, was isolated from a culture of a marine toxigenic dinoflagellate Prorocentrum mexicanum PM01. Strain PM5-8T grew at 15-35 °C (optimum, 25-30 °C) and pH 6-11 (optimum, 7.5-8). Cells required at least 1.5% (w/v) NaCl for growth, and can tolerate up to 7.0% with the optimum of 4%. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the strain PM5-8T is closely related to members of the genus Hoeflea, with high sequence similarities with Hoeflea halophila JG120-1T (97.06%) and Hoeflea alexandrii AM1V30T (97.01%). DNA-DNA hybridization values between the isolate and other type strains of recognized species of the genus Hoeflea were between 11.8 and 25.2%, which is far below the value of 70% threshold for species delineation. The DNA G + C content was 50.3 mol%. The predominant cellular fatty acids of the strain were identified as summed feature 8 (C16:1 ω7c and/or C16:1 ω6c; 51.5%), C18:1 ω7c 11-methyl (20.7%), C16:0 (17.2%) and C18:0 (5.7%). The major respiratory quinone was Q-10. Polar lipids profiles contained phosphatidylcholine, phosphatidylglycerol, sulfoquinovosyl diacylglycerol, phosphatidylmono- methylethanolamine, phosphatidylethanolamine and four unidentified lipids. On the basis of the polyphasic taxonomic data presented, strain PM5-8T (= CCTCC AB 2016294T = KCTC 62490T) represents a novel species of the genus Hoeflea, for which the name Hoeflea prorocentri sp. nov. is proposed.
Asunto(s)
Organismos Acuáticos/microbiología , Dinoflagelados/microbiología , Bacterias Aerobias Gramnegativas/clasificación , ADN Bacteriano , Bacterias Aerobias Gramnegativas/química , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Metabolómica/métodos , Tipificación Molecular , Fenotipo , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
Objective: Gingivitis is caused by a mixture of Gram-positive and Gram-negative species and is characterized by inflammatory exudate in the marginal region. Probiotics have been introduced in the prevention and treatment of periodontal diseases and represent an innovative approach to maintaining oral health using beneficial bacteria when administered in adequate amounts. The mechanism of action of probiotics in the oral cavity is not fully understood but is commonly explained by a combination of local and systemic immunomodulation. The results of the studies suggest that probiotics may be useful in the prevention and treatment of gingivitis, but their effectiveness is still very questionable. Thus, more in vivo research is needed through randomized controlled studies evaluating the main periodontal clinical parameters, levels of inflammatory mediators and microbiological analyzes, especially to elucidate some still unknown mechanisms of action and to ensure the use of probiotics as an effective therapy in the prevention and treatment of gingivitis. (AU)
Objetivo: A gengivite é causada por uma mistura de espécies Gram-positivas e Gram-negativas e é caracterizada pelo exsudado inflamatório na região marginal. Os probióticos tem sido introduzido na prevenção e tratamento das doenças periodontais e representam uma abordagem inovadora para manter a saúde bucal através da utilização de bactérias benéficas quando administradas em quantidades adequadas. O mecanismo de ação dos probióticos na cavidade bucal não é totalmente compreendido, mas é comumente explicado por uma combinação de imunomodulação local e sistêmica. Os resultados dos estudos sugerem que os probióticos podem ser úteis na prevenção e tratamento da gengivite, porém sua eficácia é muito questionável ainda. Desta forma, são necessárias mais pesquisas in vivo através de estudos randomizados controlados avaliando os principais parâmetros clínicos periodontais, níveis de mediadores inflamatórios e analises microbiológicas, especialmente para elucidar alguns mecanismos de ação ainda desconhecido e para assegurar a utilização dos probióticos como terapia eficaz na prevenção e tratamento da gengivite.(AU)
Asunto(s)
Enfermedades Periodontales , Probióticos , Gingivitis , Bacterias Aerobias Gramnegativas , Bacterias GrampositivasRESUMEN
Resumen La resistencia bacteriana se ha incrementado en América Latina y el mundo, por lo que se requiere investigación y creación de nuevos antimicrobianos capaces de erradicar a los microorganismos resistentes. Se realizó una revisión acerca de nuevas cefalosporinas y sus combinaciones con un inhibidor de β-lactamasas, recopilando información de espectro, farmacocinética, farmacodinamia y estudios clínicos de las indicaciones actuales para ceftarolina, ceftazidima/avibactam y ceftolozano/tazobactam. La primera, con actividad frente a Staphylococcus aureus y Staphylococcus coagulasa negativa sensibles y resistentes a meticilina, y contra Streptococcus pneumoniae resistente a penicilina; por lo tanto, aprobada para uso en neumonía bacteriana adquirida en comunidad e infecciones bacterianas de piel y tejidos blandos. Entre las nuevas combinaciones, ceftazidima, una cefalosporina de tercera generación con actividad anti-pseudomonas, asociada a avibactam, un inhibidor de β-lactamasas, ha demostrado efectividad en el tratamiento de infecciones abdominales e infecciones urinarias complicadas. Por último, la combinación ceftolozano y el conocido tazobactam presenta acción comparable a la combinación de ceftazidima y avibactam por su actividad contra bacilos gramnegativos y, en combinación con metronidazol no presenta inferioridad a meropenem en infecciones intra-abdominales. Se presentan los estudios clínicos y las potenciales indicaciones y escenarios de uso de estas cefalosporinas.
Bacterial resistance has increased in Latin America and the world, making research and creation of new antimicrobials capable of eradicating resistant microorganisms essential. A review of new cephalosporins and their combinations with a beta-lactamase inhibitor was conducted, collecting data on the spectrum, pharmacokinetic and pharmacodynamic profile and clinical studies of the current indications for ceftaroline, and the combinations ceftazidime with avibactam and ceftolozane with tazobactam. The first one has activity against methicillin-resistant Staphylococcus aureus and coagulase negative Staphylococcus (SCoN) and against penicillin-resistant Streptococcus pneumoniae, therefore approved for use in community-acquired pneumonia and acute bacterial skin and skin structure infections. Among the new combinations, ceftazidime, a third generation cephalosporin with antipseudomonal activity, associated with avibactam, a betalactamase inhibitor, has been shown to be effective in the treatment of abdominal infections and complicated urinary infections. Finally, the combination of ceftolozane with tazobactam has comparable action to ceftazidime with avibactam due to its activity against Gram negative rods, and in combination with metronidazole they do not present inferiority to meropenem in intra-abdominal infections. The clinical studies are presented, as well as the potential indications and clinical scenarios for their use of this cephalosporins.
Asunto(s)
Humanos , Cefalosporinas/uso terapéutico , Cefalosporinas/farmacología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Ceftazidima/uso terapéutico , Ceftazidima/farmacología , Combinación de Medicamentos , Compuestos de Azabiciclo/uso terapéutico , Compuestos de Azabiciclo/farmacología , Tazobactam/uso terapéutico , Tazobactam/farmacologíaRESUMEN
Resumen Introducción: La sepsis neonatal nosocomial (SNN) es una entidad frecuente en las unidades de cuidados intensivos, donde causa una gran morbimortalidad. La ubicación más frecuente es bacteriemia, seguido de neumonía asociada a ventilador mecánico y vía urinaria. Objetivo: Conocer la etiología y localización más frecuente de la infección en el SNN. Población, Material y Métodos: Estudio retrospectivo, de prevalencias de enero a diciembre de 2015, realizado en la Unidad de Cuidados Intensivos Neonatal de un hospital de alta complejidad. Fueron incluidos todos los neonatos. Resultados: Se incluyeron 70 pacientes, se analizaron 88 episodios de SNN. La localización más frecuente fue sangre 40% de los casos, seguido de orina y aspirado traqueal en 25% respectivamente. Los microorganismos más frecuentemente aislados fueron Staphylococcus de diferentes tipos, seguido de Acinetobacter baumannii multi-resistente. La afectación del SNC fue de 32%. La mortalidad fue de 34%, elevándose a 50% ante un segundo episodio de SNN. La terapia empírica de elección fue vancomicina y carbapenem, ajustándose a antibiograma. Conclusiones: La infección más frecuente fue la bacteremia, principalmente por Staphylococcus resistentes a meticilina. La afectación del SNC fue elevada, lo mismo que la mortalidad.
Introduction: Nosocomial neonatal sepsis (NNS) is a frequent entity in intensive care units, causing great morbidity and mortality. The most frequent site is blood, followed by lungs and urine. Objective: To know the etiology and most frequent localization of infection in the NNS. Population, Material and Methods: Cross sectional study, from January to December 2015, performed in a teaching hospital. All newborns infants were included. Results: 70 patients were included, 88 episodes of NNS were analyzed. The most frequent localization was bacteremia in 40% of cases, followed by urinary tract infection and VAP in 25% respectively. The bacteria most frequently isolated were staphylococci of different types, followed by multiresistant Acinetobacter. The CNS involvement was 32%. Mortality was 34%, rising up to 50% with a second episode of NNS. The empirical therapy of choice was vancomycin and carbapenem, adjusting to antibiogram. Conclusions: The most frequent infection was bacteremia, mainly by staphylococci resistant to methicillin. CNS involvement was elevated, as well as mortality.
Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Infección Hospitalaria/microbiología , Sepsis Neonatal/microbiología , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Unidades de Cuidado Intensivo Neonatal , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Edad Gestacional , Bacteriemia/microbiología , Neumonía Asociada al Ventilador/microbiología , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/farmacologíaRESUMEN
Resumen Introducción: Las infecciones urinarias asociadas a la atención de la salud (ITU-AAS) representan un importante problema sanitario, siendo poco conocidas sus características cuando no están asociadas a cateterización urinaria u ocurren fuera de unidades de cuidados intensivos (UCI). Objetivos: Determinar las características de los pacientes con ITU-AAS, etiología y susceptibilidad antimicrobiana de las mismas, tanto asociadas a catéter (ITU-C) como no asociadas a catéter (ITU-noC), en UCI y en sala general. Materiales y Métodos: Se realizó un estudio analítico retrospectivo de corte transversal entre 2009 y 2013 en un hospital universitario de tercer nivel. Se identificaron todos los episodios de ITU-AAS, diferenciándolas en ITU-C e ITU-noC. Resultados: Se incluyeron 253 episodios de ITU-AAS, siendo más frecuentes las ITU-C (60,9%) respecto a ITU-noC. Un 37,4% de ITU-noC y 59,7% de ITU-C ocurrieron en UCI. Los microorganismos aislados más frecuentemente fueron Escherichia coli, Klebsiella pneumoniae y Enterococcus sp. El 19% de los bacilos gramnegativos fueron productores de β-lactamasa de espectro extendido, siendo su frecuencia similar en ambos grupos. Conclusión: Las co-morbilidades de los pacientes con ITU-AAS, los agentes etiológicos responsables y sus correspondientes espectros de sensibilidad, fueron similares en los grupos de ITU-C e ITU-noC, tanto en sala general como en UCI.
Introduction: Nosocomially acquired urinary tract infections (NAUTI) represent an important public health issue, but its characteristics when they are not catheter associated (CA-UTI) or when they take place outside intensive care units (ICU) are poorly understood. Objectives: To determine the patients' characteristics, etiology and antimicrobial susceptibility of NAUTI, both CA-UTI and no CA-UTI, in general ward and ICU. Methods: We conducted a retrospective analytic cross-sectional study, between 2009 and 2013, in a third level universitary hospital. All NAUTI episodes were identified, classifying them as CA-UTI and no CA-UTI. Results: We included 253 episodes of NAUTI, being CA-UTI (60,9%) more frequent than no CA-UTI. A 37,4% of no CA-UTI and 59,7% of CA-UTI were identified in ICU. The most frequently isolated microorganisms were Escherichia coli, Klebsiella pneumoniae and Enterococcus sp. A 19% of extended spectrum betalactamase producing gram negative bacilli were found, without differences between groups. Conclusion: Patients's comorbidities, microorganisms associated to NAUTI and its antimicrobial susceptibility were similar in CA-UTI and no CA-UTI, as in general ward and ICU.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Infecciones Urinarias/etiología , Cateterismo Urinario/efectos adversos , Infección Hospitalaria/etiología , Infecciones Relacionadas con Catéteres/complicaciones , Infecciones Urinarias/microbiología , Pruebas de Sensibilidad Microbiana , Infección Hospitalaria/microbiología , Estudios Transversales , Estudios Retrospectivos , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/aislamiento & purificación , Bacterias Grampositivas/efectos de los fármacos , Hospitales Universitarios , Unidades de Cuidados Intensivos , Antibacterianos/farmacologíaRESUMEN
BACKGROUND Endophytic fungi, present mainly in the Ascomycota and Basidiomycota phyla, are associated with different plants and represent important producers of bioactive natural products. Brazil has a rich biodiversity of plant species, including those reported as being endemic. Among the endemic Brazilian plant species, Vellozia gigantea (Velloziaceae) is threatened by extinction and is a promising target to recover endophytic fungi. OBJECTIVE The present study focused on bioprospecting of bioactive compounds of the endophytic fungi associated with V. gigantea, an endemic, ancient, and endangered plant species that occurs only in the rupestrian grasslands of Brazil. METHODS The capability of 285 fungal isolates to produce antimicrobial and antimalarial activities was examined. Fungi were grown at solid-state fermentation to recover their crude extracts in dichloromethane. Bioactive extracts were analysed by chromatographic fractionation and NMR and displayed compounds with antimicrobial, antimycobacterial, and antimalarial activities. FINDINGS Five fungi produced antimicrobial and antimalarial compounds. Extracts of Diaporthe miriciae showed antifungal, antibacterial, and antimalarial activities; Trichoderma effusum displayed selective antibacterial activity against methicillin-resistant Staphylococcus aureus and Mycobacterium intracellulare; and three Penicillium species showed antibacterial activity. D. miriciae extract contained highly functionalised secondary metabolites, yielding the compound epoxycytochalasin H with high antimalarial activity against the chloroquine-resistant strain of Plasmodium falciparum, with an IC50 approximately 3.5-fold lower than that with chloroquine. MAIN CONCLUSION Our results indicate that V. gigantea may represent a microhabitat repository hotspot of potential fungi producers of bioactive compounds and suggest that endophytic fungal communities might be an important biological component contributing to the fitness of the plants living in the rupestrian grassland.
Asunto(s)
Plasmodium/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Magnoliopsida/clasificación , Magnoliopsida/microbiología , Hongos Mitospóricos/efectos de los fármacos , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Antimaláricos/aislamiento & purificación , Antimaláricos/farmacología , Clima Tropical , Bioensayo , Candida/efectos de los fármacos , Endófitos/químicaRESUMEN
Resumen Introducción: La detección de bacilos gramnegativos productores de carbapenemasas es compleja, existiendo actualmente varios test disponibles. La confirmación mediante la caracterización molecular de la enzima no está disponible en todos los laboratorios del país. Objetivo: Plantear una estrategia rápida, eficiente y sencilla para la detección y confirmación de carbapenemasas en cepas de bacilos gramnegativos. Material y Métodos: Se utilizaron 39 aislados productores y ocho no productores de carbapenemasas para evaluar los test fenotípicos Carba NP, CarbAcineto NP, Blue-Carba y validar el test molecular Xpert® Carba-R directo de la colonia en comparación con RPC convencional. Resultados: La sensibilidad para Carba NP, CarbAcineto NP y Blue-Carba fue de 79,5; 87,2 y 84,6%, respectivamente; mientras que la especificidad fue de 100; 100 y 87,5%, respectivamente. La concordancia entre RPC convencional y Xpert® Carba-R fue de 100%. El límite de detección para Xpert® Carba-R fue diferente según el tipo de carbapenemasa: 40,8 ufc/reacción par KPC y NDM y 30,6 ufc/reacción para VIM. Discusión: En aislados con susceptibilidad disminuida a carbapenémicos se propone realizar un tamizaje con CarbAcineto NP, para luego caracterizar la carbapenemasa con Xpert® Carba-R y adoptar las medidas de contención específica: para cada caso.
Introduction: The detection of carbapenemase-producing gram negative bacilli is complicated, because there are available multiple options of test. The confirmation of the enzyme by molecular characterization is not available in all laboratories in our country. Objective: To propose a fast, efficient and simple strategy to detect and confirm CPB. Materials and Methods: 39 CPB isolates and 8 non-producing were used to evaluate the phenotypic test Carba NP, CarbAcineto NP and Blue-Carba, validating the test Xpert® Carba-R, to be used directly with bacterial colonies with conventional PCR. Results: The sensitivity of Carba NP, CarbAcineto NP and Blue-Carba was 79,5; 87,2 y 84,6%, respectively; and specificity was 79.5; 87.2 and 84.6%, respectively. The limit of detection of Xpert® Carba-R was different for each carbapenemasa: 40.8 ufc/reaction to KPC and NDM and 30.6 ufc/reaction to VIM. Discussion: On isolates with decreased susceptibility to carbapenems we propose to use as screening the test CarbAcineto NP, follow by Xpert®Carba-R to characterize the carbapenemase and adopt specific infection control measures.
Asunto(s)
Humanos , Proteínas Bacterianas/biosíntesis , beta-Lactamasas/biosíntesis , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Aerobias Gramnegativas/enzimología , Antibacterianos/farmacología , Fenotipo , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa , Técnicas Bacteriológicas , Sensibilidad y Especificidad , Bacterias Aerobias Gramnegativas/efectos de los fármacosRESUMEN
The aerobic degradation of aromatic compounds by bacteria is performed by dioxygenases. To show some characteristic patterns of the dioxygenase genotype and its degradation specificities, twenty-nine gram-negative bacterial cultures were obtained from sediment contaminated with phenolic compounds in Wuhan, China. The isolates were phylogenetically diverse and belonged to 10 genera. All 29 gram-negative bacteria were able to utilize phenol, m-dihydroxybenzene and 2-hydroxybenzoic acid as the sole carbon sources, and members of the three primary genera Pseudomonas, Acinetobacter and Alcaligenes were able to grow in the presence of multiple monoaromatic compounds. PCR and DNA sequence analysis were used to detect dioxygenase genes coding for catechol 1,2-dioxygenase, catechol 2,3-dioxygenase and protocatechuate 3,4-dioxygenase. The results showed that there are 4 genotypes; most strains are either PNP (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is positive) or PNN (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is negative). The strains with two dioxygenase genes can usually grow on many more aromatic compounds than strains with one dioxygenase gene. Degradation experiments using a mixed culture representing four bacterial genotypes resulted in the rapid degradation of phenol. Determinations of substrate utilization and phenol degradation revealed their affiliations through dioxygenase genotype data.(AU)
Asunto(s)
Biodegradación Ambiental , Fenoles , Dioxigenasas , Compuestos Fenólicos , Bacterias Aerobias Gramnegativas , Bacterias Anaerobias GramnegativasRESUMEN
La bacteria Raoultella planticola se ha asociado raramente con infección clínica. Entre sus manifestaciones se destacan las infecciones del tubo digestivo y la bacteriemia. La mayoría de los casos son de origen nosocomial secundarios a procedimientos invasivos o se dan en el marco de una afección neoplásica de la vía biliar. Tratada a tiempo, la infección es de curso benigno, pero no se debe desestimar esta bacteria como inocua pues tiene homología estrecha con Klebsiella spp., lo que le confiere el potencial de adquirir mecanismos de resistencia a antibióticos como los genes bla KPC. Presentamos el caso de una paciente con bacteriemia por R. planticola de origen gastrointestinal adquirida en la comunidad y tratada exitosamente en un hospital de referencia en la ciudad de Medellín.
Raoultella planticola, a bacteria found in water and soil, is rarely associated to human disease, mostly bacteremia and gastrointestinal infections. It is usually related with health care procedures or affects patients with malignant biliary disease. If properly treated, this infection is usually benign, but the germ must not be disregarded as an innocent bystander because it has homology with Klebsiella spp., and therefore the potential to acquire antimicrobial resistance mechanisms like bla KPC genes. We report the case of a patient with community-aquired R. planticola bacteremia of gastrointestinal origin.
A bactéria Raoultella planticola se há associado raramente com infecção clínica. Entre suas manifestações se destacam as infecções do tubo digestivo e a bacteriemia. A maioria dos casos são de origem nosocomial secundários a procedimentos invasivos ou se dão no marco de uma afecção neoplásica da via biliar. Tratada a tempo, o curso da infecção é benigno, mas não se deve desestimar esta bactéria como inócua pois tem homologia estreita com Klebsiella spp., o que lhe confere o potencial de adquirir mecanismos de resistência a antibióticos como os genes bla KPC. Apresentamos o caso de uma paciente com bacteriemia por R. planticola de origem gastrointestinal adquirida na comunidade e tratada com sucesso num hospital de referência na cidade de Medellín.
Asunto(s)
Humanos , Femenino , Bacterias Aerobias Gramnegativas , Bacteriemia , Enfermedades Gastrointestinales , BacteriasRESUMEN
BACKGROUND: The objective of the present work was to develop strategies for increasing the shelf-life of red raspberries (Rubus idaeus L.), by preventing microorganism growth. RESULTS: Fruits coated with alginate plus lemon essential oil (0.2%) or orange essential oil (0.1%) after 15 days of storage had less red skin than the remaining samples. The less red color verified in these samples was also coincident with the lower concentration of anthocyanins at the end of the experiment as well as the lower capacity for scavenging ABTS free radicals or quenching singlet oxygen. Cyanidin and pelargonidin glucosides were found in raspberries fruits. The edible coatings supplemented with the essential oil of orange either at 0.1% or 0.2% were very efficient for controlling yeast and mold growth after 15 days of storage. To control the development of aerobic mesophilic bacteria the use of essential oil of lemon 0.2% and essential oil of orange 0.1% were the most efficient. CONCLUSION: The application of the film improved post-harvest quality of raspberry, since the addition of essential oils of citrus films promoted to the inhibitory effect of fungi and bacteria growth after 15 days of storage, without changing quality parameters. © 2016 Society of Chemical Industry.
Asunto(s)
Citrus/química , Conservantes de Alimentos/química , Calidad de los Alimentos , Almacenamiento de Alimentos , Frutas/química , Aceites Volátiles/química , Rubus/química , Alginatos/química , Antocianinas/análisis , Antocianinas/química , Antibacterianos/efectos adversos , Antibacterianos/química , Antibacterianos/metabolismo , Brasil , Conservantes de Alimentos/efectos adversos , Conservantes de Alimentos/metabolismo , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/química , Frutas/microbiología , Hongos/crecimiento & desarrollo , Hongos/aislamiento & purificación , Fungicidas Industriales/efectos adversos , Fungicidas Industriales/química , Fungicidas Industriales/metabolismo , Ácido Glucurónico/química , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Ácidos Hexurónicos/química , Humanos , Valor Nutritivo , Aceites Volátiles/efectos adversos , Aceites Volátiles/metabolismo , Pigmentos Biológicos/análisis , Pigmentos Biológicos/química , Análisis de Componente Principal , Rubus/microbiología , Propiedades de Superficie , Levaduras/crecimiento & desarrollo , Levaduras/aislamiento & purificaciónRESUMEN
A resistência bacteriana a antibióticos é um grave e crescente problema de saúde pública de âmbito mundial. O principal, e mais eficiente, mecanismo de resistência aos ß-lactâmicos em bacilos Gram-negativos é a produção de ß-lactamases, que possuem a capacidade de hidrolisar o anel ß-lactâmicos e consequentemente inativar essa classe de antibióticos. Vale ressaltar, que atualmente os antibióticos ß-lactâmicos são os mais utilizados clinicamente, particularmente em infecções graves. Dentre as ß-lactamases existentes destacam-se as carbapenemases, enzimas capazes de inativar a maioria dos antibióticos ß-lactâmicos. Uma grande preocupação é o fato dessas enzimas, em sua maioria, serem codificadas por plasmídeos, o que propicia a disseminação desses genes de resistência; portanto, é de extrema importância a realização de um rápido e efetivo monitoramento da presença de patógenos portadores desses genes de resistência, para que assim se possa prevenir a disseminação desses determinantes. Foram incluídos neste estudo 230 amostras únicas de Acinetobacter e Pseudomonas aeruginosa resistentes a imipenem detectados em pacientes internados em hospitais privados da cidade de São Paulo durante o período de fevereiro a outubro de 2013. As amostras foram avaliadas quanto à hidrólise de imipenem por espectrofotometria, quanto à presença de genes de carbapenemases por PCR e sequenciamento, e quanto à clonalidade por eletroforese em campos pulsados (PFGE) ou ERIC-PCR. Foram realizados ensaios de conjugação, transformação e sequenciamento completo de plasmídeos. Dentre as amostras de Acinetobacter spp. 80% (88) foram capazes de hidrolisar o imipenem. Dentre esses 76,1% (67) foram positivos para blaOXA-51-like, 19,3% (17) foram positivos para blaOXA-72. blaOXA-23, blaOXA-482 e blaIMP-1 foram detectados isoladamente em isolados distintos. O gene blaIMP-1 foi detectado em A. ursingii inserido em integron de classe 1 e representa a primeira descrição no Brasil. Uma nova carbapenemase OXA-482-like foi detectada em A. baumanii. Utilizando-se ERIC-PCR, observou-se uma grande diversidade de grupos clonais, com o máximo de quatro isolados por grupo. Dentre as amostras de P. aeruginosa, apenas 35,3% foram capazes de hidrolisar o imipenem. Dessas amostras, 14 possuíam o gene blaSPM-1, e isolados únicos possuíam, individualmente, os genes blaIMP, blaVIM, blaKPC-2 ou blaGES-23. O gene blaKPC-2 foi detectado inserido em contexto genético diferente dos descritos anteriormente, em plasmídeo IncU de 32 Kb, mobilizável, mas não conjugativo. Esta é a primeira descrição da sequencia completa de plasmídeo albergando o gene blaKPC-2 em P. aeruginosa no Brasil. Nas demais amostras (20) com atividade hidrolítica, não foram detectados genes de carbapenemase conhecidos, o que sugere a presença de genes de carbapenemase ainda não descritos. Em três amostras foi possível obter transformantes com plasmídeos, resistentes a carbapenêmicos. As amostras com blaSPM-1 apresentaram perfis de PFGE estreitamente relacionados. Em contraste, os perfis de PFGE das amostras com potenciais novas carbapenemases apresentaram índice de similaridade de Dice inferior ix a 80%, evidenciando grande diversidade clonal. Nossos achados evidenciam que a carbapenemase não intrínseca predominante em Acinetobacterem hospitais privados da cidade de São Paulo é OXA-72, e em hospitais privados há uma grande diversidade clonal. Em P. aeruginosa, a carbapenemase predominante é SPM-1, cuja disseminação é mediada por um único clone. Há potencialmente um número significativo de novas carbapenemases em Acinetobacter e P. aeruginosa, algumas delas mediadas por plasmídeos
Bacterial resistance to antibiotics is a serious and growing public health problem worldwide. The main and most efficient mechanism of resistance to ß-lactams in Gram-negative bacilli is the production of ß-lactamases, which have the ability to hydrolyze the ß-lactam ring and consequently inactivate this class of antibiotics. It is worth mentioning that currently ß-lactam antibiotics are the most used clinically, particularly in severe infections. Among the existing ß-lactamases, carbapenemases are capable of inactivating most ß-lactam antibiotics. A major concern is that these enzymes are mostly encoded by plasmids, which facilitates the spread of these resistance genes; therefore, it is of extreme importance to carry out a rapid and effective monitoring of the presence of pathogens bearing these resistance genes, in order to prevent the dissemination of these determinants. This study included 230 unique samples of imipenem-resistant Acinetobacterand Pseudomonas aeruginosa detected in patients hospitalized in private hospitals in the city of São Paulo during the period from February to October 2013. The samples were evaluated for the imipenem hydrolysis by spectrophotometry, the presence of carbapenemase genes by PCR and sequencing, and concerning clonality by pulsed field electrophoresis (PFGE) or ERIC-PCR. Conjugation, transformation and complete sequencing of plasmids were performed. Among Acinetobacter spp. samples, 80% (88) were able to hydrolyze imipenem. Among these, 76.1% (67) were positive for blaOXA-51-like genes and 19.3% (17) were positive for blaOXA-72. The blaOXA-23, blaOXA-482 and blaIMP-1 genes were detected alone in distinct isolates. The blaIMP-1 gene was detected in A. ursingii inserted in class 1 integron and represents the first description in Brazil. A novel OXA-482-like carbapenemase was detected in A. baumanii. Using ERIC-PCR, a great diversity of clonal groups was observed, with a maximum of four isolates per group. Among P. aeruginosa samples, only 35.3% were able to hydrolyze imipenem. Of these samples, 14 had the blaSPM-1 gene, and single isolates individually possessed the blaIMP, blaVIM, blaKPC-2 or blaGES-23 genes. The blaKPC-2 gene was found inserted in a genetic context different from those described previously, in a mobilizable, but not conjugative, 32 Kb IncU plasmid. This is the first description of the complete nucleotide sequence of a plasmid harboring the blaKPC-2 gene in P. aeruginosa in Brazil. In the remaining samples (20) with hydrolytic activity, no known carbapenemase genes were detected, suggesting the presence of carbapenemase genes not yet described. In three samples it was possible to obtain transformants with plasmids, resistant to carbapenems. Samples with blaSPM-1 showed closely related PFGE profiles. In contrast, the PFGE profiles of the samples with potential new carbapenemases showed Dice similarity index lower than 80%, evidencing a great clonal diversity. Our findings show that the predominant non-intrinsic carbapenemase in Acinetobacter in the city of São Paulo is OXA-72, and in private hospitals there is great clonal diversity. In P. aeruginosa, the predominant carbapenemase is SPM-1, the spread of this enzyme is mediated by a single clone. There are potentially a significant number of new carbapenemases in Acinetobacter and P. aeruginosa, some of them plasmid mediated
Asunto(s)
Acinetobacter/metabolismo , Genotipo , Fenotipo , Pseudomonas aeruginosa/metabolismo , Antiinfecciosos , Carbapenémicos , Resistencia a la Enfermedad , Bacterias Aerobias Gramnegativas , PlásmidosRESUMEN
Background: Urinary tract infections (UTIs) caused by extended-spectrum betalactamases (ESBL) are an increasingly common problem. Aim: To develop an association model to allow an early detection of ESBL-producing microorganisms. Methods: A prospective observational cohort study was undertaken among patients admitted with a diagnosis of culture-proven UTI to the Internal Medicine Ward of the Hospital Naval Almirante Nef between February and November, 2011. Patients with polimicrobial cultures were excluded from analyses, which was undertaken using multiple logistic regression. Results: Two-hundred and forty-nine patients were analysed and 35 (14%) presented an ESBL-producing microorganism. Seventy-one percent were female and the mean age was 70,7 ± 16,9 years. A history of a recent hospitalization (< 3 months) or institutionalization (p = 0.027), previous infections by an ESBL-producing bacteria (p < 0.001), recent antimicrobial use (p = 0.013) and metastatic cancer (p = 0.007) were independently associated with a current UTI with an ESBL-producing pathogen. Discussion: Our findings are similar to those found in other populations. This tool offers assistance to clinicians who need to choose an appropriate antimicrobial therapy. This model needs to be validated prior to implementation.
Introducción: La infección del tracto urinario (ITU) por microorganismos productores de β-lactamasas de espectro extendido (BLEE) es un problema infectológico creciente. Objetivo: Determinar factores de riesgo predisponentes a infecciones por microorganismos productores de BLEE. Pacientes y Método: Cohorte prospectiva de pacientes > 18 años ingresados al Servicio de Medicina Interna del Hospital Naval Almirante Nef de Viña del Mar desde febrero a noviembre de 2011 con diagnóstico de ITU confirmado en un urocultivo. Se excluyeron pacientes con urocultivos polimicrobianos. El análisis se hizo mediante una regresión logística múltiple. Resultados: Se analizaron 249 pacientes, 35 (14%) presentaron un microorganismo productor de BLEE. El 71% fueron mujeres y la edad promedio 70,7 ± 16,9 años. El antecedente de hospitalización en los últimos tres meses o el vivir institucionalizado (p = 0,027), la infección por bacteria productora de BLEE previa (p < 0,001), el uso de antimicrobianos recientes (p = 0,013) y el antecedente de cáncer metastásico (p = 0,007) se asociaron a la producción de BLEE. Discusión: Los factores encontrados en la presente cohorte están de acuerdo a lo descrito en otras poblaciones. Esta herramienta ofrece asistencia para el médico clínico en la selección de la antibioterapia más apropiada. Es necesario validar este modelo previo a su implementación.
Asunto(s)
Humanos , Masculino , Femenino , Anciano , Infecciones Urinarias/microbiología , beta-Lactamasas/metabolismo , Bacterias Aerobias Gramnegativas/enzimología , Bacterias Grampositivas/enzimología , Estudios Prospectivos , Factores de Riesgo , Infecciones Comunitarias Adquiridas/microbiologíaRESUMEN
Introducción: La espondilodiscitis (ED) implica prolongados períodos de hospitalización, de latencia diagnóstica y riesgo de complicaciones a largo plazo. No existen publicaciones recientes en Chile al respecto. Objetivos: Caracterizar un grupo de pacientes con ED. Pacientes y Métodos: Serie clínica, que incluyó pacientes en un período de ocho años. Resultados: 37 pacientes, 37,8% mujeres y 62,2% hombres, con promedio etario 66,8 años; 64,9% adultos mayores, 35,1% diabéticos y 21,6% con co-morbilidad urológica. Los principales síntomas fueron dolor y fiebre. 89,2% tuvo elevación de VHS. 86,5% contó con resonancia magnética, que siempre fue confirmatoria, siendo la columna lumbar la localización más frecuente (43,2%). Se identificó etiología en 28/37 pacientes: en 71,4% cocáceas grampositivas (Staphylococcus aureus predominantemente), sólo en 10,7% M. tuberculosis. Staphylococcus aureus estuvo asociado a co-morbilidades médicas en forma significativa (p < 0,05) y el grupo de bacilos gramnegativos a historia hepatobiliar y/o intestinal (p < 0,05). El método de mayor rendimiento fue el cultivo obtenido por punción quirúrgica. El tratamiento antimicrobiano fue indicado en promedio por 63,8 días (IQR 53-72), con reacciones adversas en 18,9%. La estadía hospitalaria fue 38,9 días promedio, no existiendo fallecidos durante este período. 18,9% presentó secuelas motoras. Discusión: La mayoría de pacientes con ED correspondió a adultos mayores, siendo S. aureus la principal etiología. Hubo una baja frecuencia de M. tuberculosis. Resultó considerable la magnitud de efectos adversos asociados a la terapia antimicrobiana y las complicaciones neurológicas.
Background: Spondylodiscitis (SD) involves long periods of hospitalization, diagnostic latency and risk of long-term complications. No updated series are available in Chile and a change in demographic features and etiology is suspected. Aim: To characterize a group of patients with SD. Patients and Methods: Clinical series including patients over an 8 year period. Results: We identified 37 patients; 37.8% women and 62.2% men (mean age 66.8 years); 64.9% were elderly; 35.1% had diabetes and 21.6% urological comorbidity. Main symptoms were pain and fever. Erythrocyte sedimentation rate was elevated in 89.2%, and 86.5% patients had MRI, which was always confirmatory. Lumbar spine was the most common site of infection (43.2%). Etiology was identified in 28/37 patients: 71.4% yielded grampositive cocci (Staphylococcus aureus predominantly), Mycobacterium tuberculosis was identified in only 10.7%. Staphylococcus aureus was associated to medical comorbidities (p < 0,05) and gramnegative bacilli to hepatobiliar or intestinal symptoms (p < 0,05). Culture obtained by a surgical procedure had the highest yield. The average duration of antibiotic therapy was 63.8 days (IQR 53-72). Treatment-related side effects were detected in 18.9% of patients. The average hospital stay was 38.9 days. No deaths occurred during hospitalization. Motor sequelae were present in 18.9% of this series. Discussion: Most patients with SD were older adults. Staphylococcus aureus was predominant and M. tuberculosis was uncommon. Antibiotic side effects were relevant as well as the neurological complications.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Discitis/microbiología , Discitis/epidemiología , Osteomielitis/microbiología , Osteomielitis/epidemiología , Enfermedades de la Columna Vertebral/microbiología , Enfermedades de la Columna Vertebral/epidemiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Discitis/terapia , Comorbilidad , Chile/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Distribución por Sexo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Hospitales Generales/estadística & datos numéricosRESUMEN
The microbiota associated with failed implants includes Pseudomonas and Gram-negative enteric rods. The present study reports a case of Escherichia coli associated to early implant failed that was resistant in vitro to doxycycline, amoxicillin, metronidazole, and clindamycin, but was susceptible in vitro to ciprofloxacin and aminoglycosides. The literature concerning the prevalence of the opportunistic microorganisms in early implant failure and peri-implantitis patients, and the usual treatment of these patients harboring Pseudomonas and enteric rods was also revised.
La microbiota asociada con los implantes fallidos incluye Pseudomonas y bacilos entéricos Gram-negativos. En el presente estudio se informa acerca de un caso de Escherichia coli asociada a un fallo temprano del implante resistente in vitro a la doxiciclina, amoxicilina, metronidazol y clindamicina, pero susceptible in vitro a ciprofloxacina y aminoglucósidos. Se realizó una revisión de la literatura sobre la prevalencia de los microorganismos oportunistas en pacientes con insuficiencia temprana del implante y periimplantitis, y el tratamiento habitual de estos pacientes portadores de Pseudomonas y bacilos entéricos.
Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Implantes Dentales/microbiología , Periimplantitis/microbiología , Bacterias Aerobias Gramnegativas/metabolismo , Insuficiencia del Tratamiento , Bacterias Gramnegativas/efectos de los fármacosRESUMEN
CONTEXT: Brazilin is a major active principle of Caesalpinia sappan L. (Leguminosae or Fabaceae). For industry aspects, brazilin-rich extract (BRE) has been prepared and standardized to contain 39% w/w brazilin. BRE may have more advantages than brazilin in term of a lower-cost production process. OBJECTIVES: To investigate the antioxidant, antibacterial, and anti-inflammatory activities of BRE. MATERIAL AND METHODS: BRE was prepared by a simple one-step purification of the crude ethanol extract of C. sappan heartwood (CSE) using a Diaion® HP-20 column. The antioxidant activities were determined using three methods, including DPPH radical scavenging, reducing power, and ß-carotene bleaching assays, at concentration ranges of 1-10, 10-100, and 10-100 µg/mL, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of BRE (15.6-1000 µg/mL) against Gram-positive and Gram-negative bacteria were determined by the broth microdilution method. Anti-inflammatory activity of BRE (0.1-5 µg/mL) was evaluated as anti-denaturation activity using bovine serum albumin as a substrate. RESULTS AND DISCUSSION: On the basis of ß-carotene bleaching assay, BRE showed antioxidant activity with an EC50 value of 60.5 µg/mL, which was almost equal to that of pure brazilin (52.1 µg/mL). Gram-positive bacteria were more sensitive to all tested samples than Gram-negative bacteria. BRE possessed higher antibacterial activities than CSE, but lower than brazilin. MIC/MBC values of 62.5-125/125 and 250-500/250-500 µg/mL were obtained for BRE against Gram-positive and Gram-negative bacteria, respectively. A low concentration (0.1 µg/mL) of brazilin, BRE, and CSE showed anti-inflammatory activity by inhibiting protein denaturation up to 46.8, 54.1, and 61.9%, respectively.
Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Benzopiranos/farmacología , Caesalpinia , Extractos Vegetales/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/normas , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/normas , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/normas , Benzopiranos/química , Benzopiranos/aislamiento & purificación , Benzopiranos/normas , Compuestos de Bifenilo/química , Caesalpinia/química , Relación Dosis-Respuesta a Droga , Etanol/química , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Fitoterapia , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/normas , Plantas Medicinales , Desnaturalización Proteica , Albúmina Sérica Bovina/química , Solventes/química , beta Caroteno/químicaRESUMEN
Prevotella intermedia é um microrganismo anaeróbio Gram negativo, considerado um dos agentes etiológicos de doenças periodontais. Tendo em vista que o biofilme subgengival é um dos seus principais habitats, qualquer quebra na homeostase do meio pode favorecer seu desenvolvimento e consequente dano aos tecidos atingidos. Diversas pesquisas vêm sendo realizadas a fim de identificar o papel deste microrganismo nas doenças periodontais. Assim, este trabalho teve por objetivo revisar a literatura para coletar informações sobre as características e efeitos de Prevotella intermedia no contexto saúde-doença periodontal. A busca foi realizada nas bases de dados PubMed e Lilacs, bem como através de uma busca aleatória. De um total de 47 artigos incluídos, alguns principais resultados puderam ser destacados: Prevotella intermedia está fortemente associada ao quadro de doenças periodontais e suas características favorecem o acometimento e intensificação de doenças diversas. Além disso, este microrganismo é capaz de produzir pigmentos e uma variedade de enzimas as quais favorecem danos aos tecidos periodontais. Existem várias características que aumentam a patogenicidade e virulência deste microrganismo, como por exemplos a sua cápsula polissacarídica, a presença de enzimas protetoras contra o oxigênio, a presença e produção de proteases, além da estimulação de fatores de crescimento no hospedeiro. Não há consenso na literatura acerca da relação de causa-efeito entre presença de Prevotella intermedia e diabetes. Contudo, este microrganismo parece estar envolvido no quadro de pacientes HIV positivo. Por fim, é importante salientar que Prevotella intermedia pode adquirir resistência a alguns tipos de antibióticos, e, por isso, o seu controle é um desafio à clínica atual...
Prevotella intermedia is a Gram negative anaerobic microorganism, considered one of the etiologic agents of periodontal diseases. Taking into account that the subgingival biofilm is its major habitat, any break of the environment homeostasis may lead to the development of the microorganism and consequent damage to the surrounding tissues. Several researches have been conducted in order to identify the role of this microorganism in the periodontal diseases. Thus, this study aimed to review the literature in an attempt to collect information about the characteristics and effects of Prevotella intermedia in the periodontal healthdisease context. The search was performed in the PubMed and Lilacs databases, as well as under a random search. From a total of 47 included articles, some major results could be drawn: Prevotella intermedia is strongly related to the occurrence of periodontal diseases, and its characteristics lead to the incidence of several diseases. Moreover, this microorganism is able to produce pigments and a variety of enzymes, which potentiate the damage of periodontal tissues. There are several characteristics that increase the pathogenicity and virulence of this microorganism, including the polyssacharidic capsule, the presence of protective enzymes against oxygen, the presence and production of proteases, as well as the stimulation of grow factors in the host. There is no consensus in the literature regarding the cause-effect relationship between the presence of Prevotella intermedia and diabetes. However, this microorganism seems to be involved in the occurrence of HIV-positive people. Lastly, it is worth to mention that Prevotella intermedia may acquire strength to some antibiotic types, and, therefore, its control is a challenge to the current clinic...
Asunto(s)
Enfermedades Periodontales , Prevotella intermedia , Virulencia , Bacterias Aerobias GramnegativasRESUMEN
Objetivo. Caracterizar un brote de infección o colonización por Acinetobacter baumannii. Materiales y métodos. Se llevó a cabo un estudio de 37 pacientes con diagnóstico de infección o colonización por A. baumannii hecho por cultivo positivo para dicho germen, entre enero de 2009 y diciembre de 2010. Los pacientes fueron caracterizados sociodemográfica y clínicamente. Se describió la frecuencia de potenciales factores de riesgo para infección o colonización por A. baumannii. Resultados. El 86 % de los pacientes presentó algún tipo de farmacorresistencia múltiple, siendo la más común la extendida a los carbapenems. Los potenciales factores de riesgo para infección o colonización más frecuentemente encontrados, fueron procedimientos invasivos (100 %), hospitalización en la unidad de cuidados intensivos (89,2 %), estancia hospitalaria prolongada (75,6 %), infección previa por otro microorganismo (51,4 %) y desnutrición (40,5 %). En cuanto a los potenciales factores de riesgo para desenlace fatal, se encontraron choque séptico (72,2 %), aislamientos con farmacorresistencia múltiple (86 %) y más de un aislamiento de A. baumannii. Conclusiones. Los principales hallazgos de este trabajo fueron la presencia de farmacorresistencia múltiple y de potenciales factores de riesgo para infección o colonización por A. baumannii en la población estudiada. La mortalidad fue de 48,4 %, principalmente por choque séptico (72,2 %), similar a lo descrito por otros autores. Las estrategias de reforzamiento de la limpieza y desinfección, especialmente la higiene de manos, han demostrado ser medidas efectivas para la prevención y el control de brotes por A. baumannii, por lo cual se recomienda la implementación y el estricto cumplimiento de dichas estrategias en el medio hospitalario.
Materials and methods: This is a case series of 37 patients with the diagnosis of infection/colonization by Acinetobacter baumannii by positive culture for this organism that occurred between January 2009 and December 2010. Patients were characterized clinically, socially and demographically. The frequency and potential risk factors for infection/colonization by Acinetobacter baumannii are described. Results: 86% of patients had some type of multidrug resistance, the most common being resistant to carbapenems. Potential risk factors most frequently found were: invasive procedures (100%), ICU stay (89.2%), prolonged hospital stay (75.6%), previous infection with another microorganism (51.4%), and malnutrition (40.5%). As for potential risk factors for fatal outcome we found: septic shock (72.2%), multidrug isolates (86%), and more than one isolate of Acinetobacter baumannii. Conclusions and recommendations: The main findings of this study were the presence of multidrug resistance and potential risk factors for infection/colonization by Acinetobacter baumannii in the study population. Mortality rate was 48.4%, due mainly to septic shock (72.2%), similar to that described by other authors. Strategies to reinforce the cleaning and disinfection, especially hand hygiene measures, have proven effective for the prevention and control of outbreaks by Acinetobacter baumannii; therefore, the implementation and strict compliance of these strategies are recommended in the hospital setting.
Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Acinetobacter baumannii , Infecciones por Acinetobacter , Brotes de Enfermedades , Resistencia a Múltiples Medicamentos , Bacterias Aerobias GramnegativasRESUMEN
This study aimed to isolate and identify Aeromonas bacteria from samples of oysters and water, by microbiological and molecular methods. Identification of Aeromonas was performed by the conventional method and by PCR and species characterization was performed by identification key Aerokey II and by RFLP-PCR of 16S rDNA. 59 (98.3%) samples of oysters and 15 (75%) samples of water contaminated by Aeromonas bacteria were identified. Of the 74 isolates of Aeromonas spp. obtained by microbiological analysis, 53 (71.62%), 38 (65.51%) oyster samples and 15 (100%) of water samples confirmed the characterization of the genus by molecular technique. As to biochemical species identification, 59.3% (n = 35) and 40.6% (n = 24) of isolates from Aeromonas sp. obtained from oyster samples were rated as A. hydrophila and A. caviae, respectively; and from isolates obtained from water samples, 60% (n = 9) were classified as A. hydrophila and 40% (n = 6) as A. caviae; however, only the A. hydrophila was confirmed by genetic sequencing. Regarding the classification by RFLP-PCR 16S rDNA, patterns of nonspecific bands were obtained, making it impossible to identify the species by this technique. The large number of oyester samples contaminated with Aeromonas spp. and identification of A. hydrophila, demonstrate that this mollusk might present a risk to consumer health, mainly because it is consumedraw and is to a potentially pathogenic micro-organism to humans.
Objetivou-se isolar e identificar bactérias do gênero Aeromonas de amostras de ostras e de água, pelos métodos microbiológico e molecular. A identificação do gênero Aeromonas foi realizada pelo método convencional e pela técnica da PCR e a caracterização das espécies foi realizada pela chave de identificação Aerokey II e pela técnica de RFLP-PCR do 16S rDNA. Foram identificadas 59 (98,3%) amostras de ostras e 15 (75%) amostras de água contaminadas por bactérias do gênero Aeromonas. Dos 74 isolados de Aeromonas spp. obtidos pela análise microbiológica, 53 (71,62%), 38 (65,51%) de amostras de ostras e 15 (100%) de amostras de água, confirmaram a caracterização do gênero pela técnica molecular. Quanto a identificação bioquímica das espécies 59,3% (n=35) e 40,6% (n=24) dos isolados de Aeromonas sp. obtidos das amostras de ostras foram classificados como A. hydrophila e A. caviae, respectivamente; e para os isolados obtidos das amostras de água, 60% (n=9) foram classificados como A. hydrophila e 40% (n=6) como A. caviae; entretanto, somente a A. hydrophila foi confirmada pelo sequenciamento genético. Quanto a classificação através da RFLP-PCR 16S rDNA, foram obtidos padrões de bandas inespecíficos, impossibilitando a identificação das espécies por esta técnica. O grande número de amostras de ostras contaminadas com Aeromonas spp. e a identificação da A. hydrophila demonstram que este molusco pode oferecer risco à saúde dos consumidores, principalmente por ser consumido innatura e se tratar de um micro-organismo potencialmente patogênico para o ser humano.
Asunto(s)
Animales , Aeromonas/patogenicidad , Efectos de la Contaminación del Agua/análisis , Ostreidae/microbiología , Agua/análisis , Bacterias Aerobias Gramnegativas/patogenicidad , Reacción en Cadena de la Polimerasa/métodosRESUMEN
This study aimed to isolate and identify Aeromonas bacteria from samples of oysters and water, by microbiological and molecular methods. Identification of Aeromonas was performed by the conventional method and by PCR and species characterization was performed by identification key Aerokey II and by RFLP-PCR of 16S rDNA. 59 (98.3%) samples of oysters and 15 (75%) samples of water contaminated by Aeromonas bacteria were identified. Of the 74 isolates of Aeromonas spp. obtained by microbiological analysis, 53 (71.62%), 38 (65.51%) oyster samples and 15 (100%) of water samples confirmed the characterization of the genus by molecular technique. As to biochemical species identification, 59.3% (n = 35) and 40.6% (n = 24) of isolates from Aeromonas sp. obtained from oyster samples were rated as A. hydrophila and A. caviae, respectively; and from isolates obtained from water samples, 60% (n = 9) were classified as A. hydrophila and 40% (n = 6) as A. caviae; however, only the A. hydrophila was confirmed by genetic sequencing. Regarding the classification by RFLP-PCR 16S rDNA, patterns of nonspecific bands were obtained, making it impossible to identify the species by this technique. The large number of oyester samples contaminated with Aeromonas spp. and identification of A. hydrophila, demonstrate that this mollusk might present a risk to consumer health, mainly because it is consumedraw and is to a potentially pathogenic micro-organism to humans. (AU)
Objetivou-se isolar e identificar bactérias do gênero Aeromonas de amostras de ostras e de água, pelos métodos microbiológico e molecular. A identificação do gênero Aeromonas foi realizada pelo método convencional e pela técnica da PCR e a caracterização das espécies foi realizada pela chave de identificação Aerokey II e pela técnica de RFLP-PCR do 16S rDNA. Foram identificadas 59 (98,3%) amostras de ostras e 15 (75%) amostras de água contaminadas por bactérias do gênero Aeromonas. Dos 74 isolados de Aeromonas spp. obtidos pela análise microbiológica, 53 (71,62%), 38 (65,51%) de amostras de ostras e 15 (100%) de amostras de água, confirmaram a caracterização do gênero pela técnica molecular. Quanto a identificação bioquímica das espécies 59,3% (n=35) e 40,6% (n=24) dos isolados de Aeromonas sp. obtidos das amostras de ostras foram classificados como A. hydrophila e A. caviae, respectivamente; e para os isolados obtidos das amostras de água, 60% (n=9) foram classificados como A. hydrophila e 40% (n=6) como A. caviae; entretanto, somente a A. hydrophila foi confirmada pelo sequenciamento genético. Quanto a classificação através da RFLP-PCR 16S rDNA, foram obtidos padrões de bandas inespecíficos, impossibilitando a identificação das espécies por esta técnica. O grande número de amostras de ostras contaminadas com Aeromonas spp. e a identificação da A. hydrophila demonstram que este molusco pode oferecer risco à saúde dos consumidores, principalmente por ser consumido innatura e se tratar de um micro-organismo potencialmente patogênico para o ser humano. (AU)
Asunto(s)
Animales , Aeromonas/patogenicidad , Ostreidae/microbiología , Agua/análisis , Efectos de la Contaminación del Agua/análisis , Bacterias Aerobias Gramnegativas/patogenicidad , Reacción en Cadena de la Polimerasa/métodosRESUMEN
This study examined the effect of dissolved oxygen concentration on the production of biomass and metabolites with antimicrobial activity of Pseudoalteromonas sp cultured at 0, 150, 250, or 450 revolutions per minute (rev. min-1). Dissolved oxygen (D.O) was monitored during the fermentation process, biomass was quantified by dry weight, and antimicrobial activity was assessed using the disk diffusion method. The bacterium Pseudoalteromonas reached similar concentration of biomass under all experimental agitation conditions, whereas antimicrobial activity was detected at 0 and 150 rev. min-1 registering 0% and 12% of D.O respectively corresponding to microaerophilic conditions. Antibiotic activity was severely diminished when D.O was above 20% of saturation; this corresponded to 250 or 450 rev. min-1. SDS-PAGE electrophoresis revealed a protein with a molecular weight of approximately 80 kilodaltons (kDa) with antimicrobial activity. Pseudoalteromonas is capable of growing under oxic and microaerophilic conditions but the metabolites with antimicrobial activity are induced under microaerophilic conditions. The current opinion is that Pseudoalteromonas are aerobic organisms; we provide additional information on the amount of dissolved oxygen during the fermentation process and its effect on antimicrobial activity.